The present invention relates to a mounting apparatus used for mounting electronic components fed from a component feeding section to a mounting member, such as a circuit board, to which the components are mounted.
In a conventional mounting apparatus of the type referred to above, a plurality of component feeding units containing electronic components are aligned side by side on a moving table at a component feeding section, and the components are taken out (removed) at predetermined positions by moving the moving table in an aligning direction. The circuit board, specifically, a component of the circuit substrate where the components are mounted, is positioned at a predetermined position by a positioning means while the positional shift of the components held by a mounting means is recognized and corrected by a recognizing means. Accordingly, the components are correctly mounted on the circuit board.
For the mounting means, as shown in FIGS. 11 and 12, a rotatable rod 43 is set in a housing 42 which is supported by a linear slide 41 in a movable fashion in the up-and-down direction, and a suction nozzle 44 for sucking and holding an electronic component 45 is provided at the lower end of the rod 43. An air switching valve 46 at the side face of the housing 42 is effective to switch between providing the suction nozzle 44 with negative pressure air for suction and holding of component 45, and positive pressure air for mounting the component 45 on the circuit board. Air pipes 47 are connected to the switching valve 46 to feed or suck the air.
As in FIG. 13, the air switching valve 46 is generally comprised of a spool 46a, pressure switching levers 46b, 46c, and a spring 46d for urging the switching levers 46b, 46c toward one another.
In order to mount the components at high speeds with high accuracy using the above-described conventional mounting apparatus, the mounting means should be made compact in size and light in weight and moreover arranged with a narrow pitch to reduce the moving distance, to thereby lessen the centrifugal force or acceleration/deceleration force acting on the components.
However, the mounting means of the above constitution has difficulty in meeting the requirements. That is, since the air pipes 47 are present and moreover, the stroke of the housing 42 in the up-and-down direction requires the air pipes 47 to be relatively long, the air pipes 47 disadvantageously interfere with the component 45 held by the nozzle 44 adjacent to the air pipes 47, thus causing positional shifting of the component 45 or resulting in the breakage of the pipes 47. If the air pipes 47 are broken, the air is not properly fed and therefore, the component cannot be held correctly or is shifted in position. Furthermore, due to the disposition of the air switching valve 46 which is a separate body in the complicated structure, it is difficult to make the mounting means compact and light-weight.